The present invention relates to a method for the photogrammetrical pick up of an object with the aid of at least one opto-electric solid-state surface sensor, the image area of which is smaller than that of the total image sought to be recorded. The point array of a reseaus (glass plate with suitable point markings distributed like a raster) covering the total image is included in the photogrammatical imaging system, and the surface sensor is arranged in the imaging space in such a manner that it images in each case at least one mesh of the reseau covering the area in the sensor image. For the opto-electric analog/digital conversion of images present in analog form, the transparent master is brought in contact with a scanning reseau and is projected, together with the scanning reseau, onto a sensor area with the aid of an objective. The sensor surface and objective are jointly displaced from reseau mesh to reseau mesh for continuous recording.
The present invention also relates to a method for the photogrammetrical pick up of a stationary object with the aid of at least one opto-electric solid-state surface sensor, the image area of which is smaller than that of the total image sought to be recorded. The point array of a reseau (glass plate with suitable point markings distributed like a raster) covering the total image is included in the photogrammetrical imaging system, and the surface sensor is arranged in the imaging space in such a manner that it images in each case at least one mesh of the reseau covering the area in the sensor image. For an opto-electric recording system for recording stationary objects, a sensor area is arranged behind the chamber reseau arranged in the image plane of the recording chamber so that the chamber reseau can be projected, together with the object to be recorded, onto the sensor area with the aid of the imaging system of the recording chamber. The sensor area is then displaced from reseau mesh to reseau mesh for the continuous recording.
These general methods are disclosed in German Pat. No. 3,428,325 incorporated herein by reference. If in this method a reseau plate covering the entire image format to be scanned is included in the imaging process, the partial-images created on the areas of the sensor blocks can be unambiguously numerically transformed into the plane of the reseau with the aid of the reseau points which are also imaged on the sensor areas within the capability of the digital image analysis system. In that case, the requirements for the physical position of the sensor blocks in the imaging space are only small and can be realized with little instrumentation effort: at least one mesh each of the reseau is also to be imaged onto the sensor areas to cover these areas; and the sensor areas are to be brought close enough to the reseau plane so that the points of the reseau, together with the object to be recorded, can be imaged with sufficient definition. Due to the transformation of the partial-images created on the image areas of the individual sensor blocks into the plane of the reseau, the total image format is obtained with high accuracy predetermined by the calibrated reseau plate.
Including a reseau in the imaging process permits, on the one hand, a high-accuracy flat-bed scanner to be constructed with little instrumentation effort. In addition, the possibility of combining into assemblies several sensor areas like a raster in an unambiguous mutual geometric relation provides the prerequisite for simultaneously picking up the entire area of an image format of, in principle, any size with simple instrumentation and, at the same time, high accuracy.
When using a flat-bed scanner for analog/digital conversion, the transparent master to be digitized is located underneath the reseau plate on a transparent base (for example, opal glass plate) and is imaged with transmitted light onto the sensor area. Sensor area and object to be imaged are carried from reseau mesh to reseau mesh for continuous exposure. By varying the magnification, the scanning rate can be changed, that is to say, the size of the image element in the master can be determined which is imaged onto a sensor element of the sensor block. In this arrangement, the mesh size and point marking density of the reseau must be matched (exchange of reseau plates).
The above-mentioned prior publication also shows the arrangement of a sensor block behind the image plane of a photogrammetrical recording system. The reseau points are imaged, together with the object to be recorded, onto the sensor area with the aid of the objective of the recording chamber. With a stationary recording arrangement, an individual sensor can be carried from reseau mesh to reseau mesh in the manner of a flat-bed scanner for continuous exposure in order to pick up the total format. Simultaneous pick up of the total format becomes possible if several sensor blocks, combined into several assemblies like a raster, are arranged behind a common reseau plate. The raster spacing of the sensor blocks in the assemblies is given, on the one hand, by the raster spacing of the reseau points and, on the other hand, will have to take into account that the light-sensitive areas of the sensor blocks, due to their construction, can only be arranged next to each other up to a certain minimum distance.
A more complete description of German Pat. No. 34 28 325 is set forth below.